/Engine/Plugins/Online/OnlineFramework/Source/Qos/Public/QosRegionManager.h
Get a sorted list of subregions within a region
void GetSubregionPreferences ( const [FString](API\Runtime\Core\Containers\FString) & RegionId, [TArray](API\Runtime\Core\Containers\TArray)< [FString](API\Runtime\Core\Containers\FString) > & OutSubregions ) const